Using an unstructured peptide as scaffold to study a consensus iron-binding motif from CyaY protein family

VAZQUEZ DS; YOME A; VIZIOLI N; GONZÁLEZ FLECHA FL; GONZÁLEZ LEBRERO MC; SANTOS J

San Javier, Tucumán

Congreso; Encuentro anual de la Sociedad Argentina de Biofísica; 2012

Sociedad Argentina de Biofísica

Proteins belonging frataxin family, which control intracellular iron homeostasis,have a cluster of acidic residues located between the N-terminal α-helix andβ1-strand that are apparently responsible for iron binding and iron exchange1.To understand how frataxin works as an iron chaperon, we studied by circular dichroism (CD), capillary zone electrophoresis (CZE) and isothermal titration calorimetry (ITC), the interaction of mono, di and trivalent metal ions with a  chimeric peptide containing a putative iron binding site from the bacterial frataxin CyaY. For this purpose, a peptide corresponding to the C-terminal α-helix from E. coli thioredoxin (wt HCT) was redesigned including the motif EExxED from the bacterial frataxin resulting an engineered 16 residues-long amphipathic peptide called pIBS, (from putative Iron Binding Site).